REM architecture changes in bipolar and unipolar depression

Abstract
Total night sleep measures and REM [rapid eye movement] sleep architecture values were compared for normal control subjects (N = 36), unipolar depressed patients (N = 36) and bipolar depressed patients (N = 22). The unipolar and bipolar patients had significantly greater fragmentation of REM periods than control subjects, and bipolar patients showed greater gragmentation of REM periods than unipolar patients. In both samples, the duration of successive REM periods was related to the total number of REM periods during sleep.